EV Archiving Exch 2010 DAG + system mailboxes
So this question has been asked mant time before so forgive me for asking for more clarification.
So I have a 8 node dag with 4 active servers on the primary site and 4 passive nodes on the DR site. Each active node hosts 4 databases and so I have 16 active databases on the primary site. Each passive node has a passive copy of each of the active databases (so that 64 passive databases on the DR site). Each active node also has a passive copy of other active node's databases.
My understanding is that each mailbox server needs a mailbox archiving task and I'd need to failover active databases to achieve this - once done I can fail the databases back to the BAU location.
My question is around the system mailboxes and how many I will need? is it one per active database = 16? or one per active mailbox server = 4?
I will have 4 x EV servers each one archiving one of the 4 mailbox servers at the primary site and I plan to configure each EV server to archive one of the passive servers on the DR site (should a database failover).
So I create a system mailbox on an active database on the primary site mailbox servers and create the archiving tasks - I then fail this database over to the DR site and create the archiving task for that server. What happens if a database fails obver that doesn't contain the system mailbox? so I now have an active database on one of the DR mailbox servers but no system mailbox for the archiving task to use.